0 Preheat oven to 400°F/200°C
1 Cut cauliflower into large pieces. Boil in a pot of water over high heat until very soft. Drain.
2 Meanwhile, thinly slice potatoes, chard, mushrooms and onion. I use a mandoline slicer to get a nice thin slice, I slice the chard into shreds with a knife. Set aside.
3 Once cauliflower is done, make the sauce by placing all ingredients into a blender. Blend until sauce is thick and creamy.
Layer your casserole in a 9 x 12 baking dish as follows, it may look too tall but it will shrink when baked:
6 about ¾ to 1 cup sauce on bottom of pan (depending on how saucy you like it)
7 1/3 of the potato slices
8 ½ of the mushrooms
9 ½ of the onions
10 ½ of the chard
11 another ¾ to 1 cup sauce (depending on how saucy you like it)
12 1/3 of the potato slices
13 other ½ of the mushrooms
14 other ½ of the onions
15 other ½ of the chard
16 another ¾ to 1 cup sauce (depending on how saucy you like it)
17 last 1/3 of the potatoes
18 top with another ¾ to 1 cup sauce (depending on how saucy you like it)
19 sprinkle with parmesan of choice
20 Cover with foil and bake at 400°F (200°C) for 35 minutes. Remove foil and bake another 15-20 minutes or until browning on top. Allow to cool and set before cutting and serving.
